Apparatus for winding filamentary material into smooth ended packages



March 2, 1965 R. H. SPEAKMAN APPARATUS FOR WINDING FILAMENTARY MATERIAL INTO SMOOTH ENDED PACKAGES 2 Sheets-Sheet 1 Filed Aug. 7, 1963 INVENTOR Re wmo wzpr/n zflxmfi/v March 2, 1965 R H. SPEAKMAN 3,171,608

APPARATUS FOR WINDING FILAMENTARY MATERIAL INTO SMOOTH ENDED PACKAGES Filed Aug. 7, 1965 2 Sheets-Sheet 2 INVENTOR 3/ I Q 6 llwma/i ozpzmfifi mu/v ATTORNEYS United States Patent Ofiice 3,171,668 APPARATUS FOR WINDKNG FELAMENTARY MA- TERIAL INTO SMOOTH ENDED R'ACKAGES Raymond Holden Speakman, Harrogate, England, assignor to Imperial Chemical Industries Limited, London, England, a corporation of Great Britain Filed Aug. 7, 1%3, Ser. No. 300,481 Claims priority, application Great Britain, Aug. 30, $66, 29,864/59 11 Claims. (Cl. 24243) This invention is a continuationin-part of application Serial No. 131,072, filed August 14, 1961, now abandoned.

This invention relates to apparatus for continuously winding filamentary material such as yarns, tows and monofilaments at high speed into smooth ended cylindrical packages.

The term yarns is used herein in a broad sense to include all filamentary material capable of being wound onto a bobbin.

In the flat winding of yarn, the yarn is frequently directed onto a rotating receiving bobbin by a guide which reciprocates in an axial direction in an attempt to produce a constant helix angle of lay of yarn on the bobbin and thereby produce a uniformly cylindrical package.

Ideally such an arrangement requires that the guide shall reverse its direction of travel instantaneously at the end of each traverse of the package, however, this condition has been difiicult to approach because of the infinitely large forces that would be required to effect the instantaneous complete reversal of travel direction of a guide having finite mass. Therefore, several forms of complex mechanical arrangements have been devised for efiecting this reversal in as short an interval as is possible while maintaining the forces involved within the limits of the mechanical strength of the apparatus.

Examples of prior art apparatus include those in which the guide is controlled by a cam, generally of the barrel type, having a linear track on a majority of its periphery to impart a constant guide velocity axially of the package. Additionally, a short parabolic or otherwise curved sec tion is provided connecting the straight portions of the cam track. The curved section etfects the desired reversal at the end of each package traverse. Other examples include those having various counterbalancing weights and springs mounted on the guide which efiect a speed-up of the guide with respect to the cam follower as the follower slows for a reversal. In each case the cammed reversal effects the direction change of the guide but since the cammed reversal requires a significant interval or" time this procedure results inevitably in a region at each end of the package in which the guide is traveling at a speed different from the constant speed at which it traverses a majority of the package. When the guide moves more slowly adjacent its reversal point a ridge of yarn tends to be produced due to the relatively constant winding speed. Additionally, this effects a reduction of the helix angle adjacent the package ends resulting in a substantial reduction in the stability of the package at the ends. Prior art methods have sought to alleviate this undesirable ridging and reduction in stability by ironing the surface of the package continually with a roller which may conveniently also serve as the package drive means, but the general result obtained is a package with hard ends and irregularly shaped sides.

This problem is more pronounced at high yarn winding speeds since to produce an adequate helix angle of lay for stability, the traverse guide must travel with correspondingly high velocity, and to maintain reversal forces within the mechanical strength of the machine the shape of the cam track at reversal must be modified to give an increased reversal time.

The problem of the increasing departure from linearity $111,508 Patented Mar. 2, 1965 with increasing speed is most acute in the commonly used type of take up in which a large number of yarn guides are mounted upon a single long traverse bar, the reciprocating motion of which is controlled by means of a single cam at one end of the traverse bar. This difliculty is due to the much larger mass of the reciprocating parts with this arrangement which may reach 15 or 20 lb. and impose correspondingly large forces at reversal. With such arrangements when used for other than the very lowest speeds it is accordingly necessary to use a very heavy and strongly made cam and to provide this with a track whose curvature at the reversal points is relatively gradual so that excessive forces are avoided. This results in excessive ridging on the package at the ends of the traverse.

It is therefore a primary object of this invention to provide a novel guide system especially arranged to avoid the unsatisfactory package build heretofore associated with high speed traverse bar Winding systems.

It is a further object of this invention to provide a yarn guiding system for high speed yarn winding in which the rapidity of reversal of the guide is largely independent of the degree of reversal of curvature of the traverse bar operating cam.

Another object of the invention is to provide a novel guide system in which the yarn is guided from the outer end of an ela-stomeric mass which is secured to a cam operated traverse bar.

Yet another object of this invention is the provision of a yarn guide comprising a pair of clastomeric legs projecting outwardly from a traverse bar, including means for guiding the yarn between the outer ends of the resilient legs and stop means mounted adjacent the legs to limit the pivoting of the legs.

A further object of the invention is to provide a guide of the type described in which the mass, length and composition of the guide legs and the positioning of the stop means is such that the guide will be substantially critically damped and thus will not repeatedly oscillate after changing direction at the end of the package.

A more general object of the invention is to provide a guide of the type described in which the yarn guiding means will continue to travel in its direction at a substantially constant speed for a short space of time after the traverse bar has reversed its direction with respect to the package being wound.

These and other objects of this invention will appear and be more fully discussed in the detailed explanation which follows; reference being made to the attached drawings in which a preferred embodiment of the invention is shown, not to limit the scope of the invention in any manner, but in order to more Iucidly illustrate the principles thereof.

In the drawing:

FIGURE 1 is a perspective view of the novel yarn guide mounted on a traverse bar:

FIGURE 2 is a sectional view taken substantially along the line 2-2 of FIGURE 1;

FIGURE 3 is a sectional view taken substantially along the line 33 of FIGURE 2 (the traverse bar having been removed for clarity).

Now with particular reference to the figures, a thread guiding system embodying the principles of this invention is indicated at 10 carried on a traversing bar 12, adjacent the filament receiving package of a conventional high speed winding machine (not shown). The traverse bar 12 is mounted with its longitudinal axis paralleling that of the receiving package and is arranged to reciprocate axially of the package preferably in a horizontal plane. Preferably, as aforementioned, a plurality of guiding systems 10 are mounted on the bar 12 in side by side relationship to guide thread onto a plurality of packages. The bar 12 is preferably reciprocated as by a pin 16 and barrel cam 18 arrangement although the particular form illustrated is merely exemplary being that any means can be employed that will cause the bar to reciprocate axially of the package with a constant speed and a relatively sharp reversal of direction. It is desirable that the bar be moved at constant velocity so that the thread guide will deposit an even lay of filament from one end of the package to the other.

The novel guide assembly includes a beam moulding 20, a carrier 22 and a thread guide 24. In the preferred embodiment shown the beam moulding 2%? is composed of an elastomeric material such as Vulcaprene dipped black butyl rubber having a shore hardness of Of course the exact dimensions and composition of the moulding will depend on the speed and length of the oscillation for which the particular guide system is designed so that the guide will be substantially critically damped as to eliminate repeated oscillation after a revcrsal. The moulding generally comprises a pair of slightly spaced opposed L-shaped legs 26 integrally projecting from a base portion 28 formed of the same material. As" shown the ends 30 of the legs 26 are directed toward one another as to leave smooth faces 32 at the inner extent of each.

The thread guide 24 comprises an arcuate segment of a more rigid material suchas mild steel. The thread guide 24 preferably is bent twice adjacent its arcuately outer ends to form L-shaped tabs 31. Adjacent its midpoint, the guide has a circular opening 33 formed therethrough so close to the outer arcuate periphery 34 of the guide as to intersect it and provide an en rance 36 to the opening. Additionally, one or more additional holes 38 maybe formed through the guide to receive a locating tool during the fabrication of the guide system as more fully set forth hereinafter.

The carrier 22 as illustrated especially in FIGURES 2 and 3 comprises a generally rectangular plate 44) having a generally rectangular opening 42 formed through the central portion thereof; a U-shaped section 44 having two opposed inwardly directed legs 46 spaced apart by an outer lateral portion 48 having a rectangular opening 5t} formed therethrough, similar in orientation and dimension to opening 42; and a generally Y-shaped stop member 52 which projects through the openings 54. As best illustrated in FIGURE 3 the three portions of the carrier 22 are associated with one another as by spot welding so that the opening 50 through the -.U-shaped section 44 directly overlies the opening 42 through the rectangular plate and the Y-shaped portion projects through the superposed openings and has its singular leg 56 outermost.

The Y-shaped stop preferably has a laterally directed tab 58 at the outeriend of each paired leg 66 which is secured as by spot welding to the inner surfaces of the lateral portion 48 adjacent the periphery of the hole 543.

The guiding system It) is preferably assembled by conventional moulding techniques which may include apand the bobbin caused to rotate at a constant high speed.

The cam 18, which may be driven from the winding apparatus, engages the pin 16 and causes the bar 12 carrying the novel guide assembly 10 to oscillate back and forth along the package at a constant speed, depositing a uniform lay of filament with each pass.

It can be seen that as the bar reaches one end of its path and is caused to slow down, reverse direction, and regain constant speed in the opposite direction that the resilient, elastomeric legs of the beam will continue to travel in the first direction under the force of inertia until the smooth inner surface of the leg extending toward the first travel direction contacts the singular leg of the positive l -shaped stop. This last instance occurs after the bar 12 has begun to pick up speed in the second, opposite traversing direction. Therefore as the resilient force stored in the beam legs beginsto return the guide to its null position shown this velocity is added to the approaching steady state velocity of the bar having the net efiect of causing the filament to be carried by the guide at a constant velocity for almost the entire cycle including the reversals at each of which an action similar to that just described occurs. This, of course, results in the achieving of a much smoother sided, constant helix package than has heretofore been possible.

The movement imparted to the guide is best shown by the following summation.

(1) The guide is carried in the null position shown in the figures at a constant sped intermediate the end points of its path.

(2) Near an end point the traverse bar reverses direction but the guide continues on carried between the resilient legs as the legs build up a restoring force and one of them hits the positive stop.

(3) During 2 the traverse bar has begun to gain speed in its reverse direction and now as the restoring force moves the guide to its null position the velocity imparted is added to the velocity imparted by the bar to the guide to very closely approximate the desired constant velocity.

(4) As the restoring force diminishes and the guide returns to its null position the bar has attained the constant velocity.

The proper spacing of the legs from each other and the stop and leg length and weight for achieving a critically damped thread guide can best be found by experiment, for the resilient parts of the guide are required to propriately positioning the guide 24 and carrier 22 adjacent a mould configured to form the beam 2t} and then.

injecting the desired moulding composition into the mould so that the plate 40 of the carrier and the L-shaped tabs 31 of the guide are entrapped in the composition. If.

necessary the composition can be cured and the beam 20 coated with a suitable antioxidizing compound to extend the useful life of the assembly.

From FIGURES 1 and 3 it can be seen that in its assembled form the Y-shaped stop 52 of the guide system has its singular leg 56 in position midway between the smooth end surfaces of the spaced outer portions 30 of the beam L-shaped legs 26. The guide assembly 10 is suitably mounted to the traverse bar 12 by receiving the bar in the U-shaped section 44 and securing it there by bolts 62. which pass through the inner portions of the legs 46 and over the bar 12 damp out, not only any tendency of the guide to oscillate but also to absorb vibrations in the traverse bar itself, which, due to its length and mass even when made of steel, is not completely inelastic suffering a small degree of compression and extension as it oscillates to and fro.

In the arrangement shown the rapidity of reversal of the guide and hence the uniformity of build obtained in the package is limited only by mechanical strength and weight, considerations of the guide arm and the stops, and is now completely dissociated with the degree of curvature at reversal on the cam track. The latter can therefore be made much less severe than is possible with the usual arrangement in which the guide is rigidly connected to the traverse bar, and reduced wear and longer life of the cam and traverse bar can accordingly be obtained.

The technique described herein has been found particularly valuable in the collection of filaments of synthetic polymers obtained by melt or solution spinning. In particular our winding process has been used for the collection of melt spun filaments of polyesters, e.g., polyethylene terephthalate, p'olyamides e.g., polyhexamethyl- We have, for example, wound an excellent package of 12 lb. weight using a traverse bar arrangement in which the cam track was designed to reverse the traverse bar velocity in a distance of 0.175. Using a yarn speed of 4500 ft./min. and 270 cycles per minute traverse guides made to either of the above methods produced excellent cheese shaped packages with clean sides. Under similar conditions with a conventional guide, the edges of the package were very hard and the sides were very irregular.

Although the beam portion of the guide assembly is preferably composed of high hysteresis butyl rubber it is contemplated that other natural or synthetic elastomeric materials having the property of quick, nearly complete recovery after flexure could be used.

It should be understood that the arrangement and configuration of the assembly shown is merely exemplary in that various modifications will readily occur to those skilled in the art, but which are fairly encompassed within the principles of this invention. Therefore, the invention should not be limited by the preferred embodiment shown, but only by the spirit and scope of the following claims.

What is claimed is:

1. A high speed winding apparatus for collecting filamentary materials on a rotating package comprising: a traverse bar disposed in a direction parallel to the axis of rotation of said package; means for reciprocating said traverse bar in said direction, filamentary guide means carried by said bar adjacent the package, said guide means comprising an elongated flexible elastomeric portion projecting outwardly from the bar and means mounted on the elastomeric portion adjacent the outer extent thereof for slidingly guiding a yarn for winding on the package.

2. Apparatus as set forth in claim 1 wherein the elastomeric portion of the guide means is a moulded beam composed of high hysteresis bu-tyl rubber having a shore hardness of 5055.

3. Apparatus as set forth in claim 1 wherein the elastomeric portion comprises two opposed L-shaped legs projecting from said bar as to have the outer portions of the legs directed toward one another, and wherein the yarn carrying means comprises a rigid member secured to each of the legs and arranged to carry a yarn outside and between the outer extent of the legs.

4. Apparatus as set forth in claim 1 additionally comprising positive means fixedly secured with respect to the bar and positioned with respect to the legs to limit the flexure thereof to a predetermined degree.

5. Apparatus as set forth in claim 4 wherein the stop means comprises a rigid member positioned between the opposed L-shaped legs.

6. A rotating package; a tra erse bar extending in a direction parallel to the rotational axis of the package; means reciprocating the traverse bar axially of the package so that the velocity of the bar is substantially constant between the end points of the reciprocation; a flexible beam mounted on the bar adjacent the package as to extend transversely from the bar; means mounted on the beam adjacent the outer extent thereof for guidingly engaging a yarn for winding on said package, the beam being of such flexibility that the yarn guiding means continues to travel at substantially constant velocity in a first direction for a finite period of time subsequent to the change in direction of the bar at the end .point of a reciprocation.

7. Apparatus as set forth in claim 6 additionally comprising positive stop means fixedly positioned w'ith respect to the bar to limit the flexure of the beam after the bar direction change.

8. Apparatus as set forth in claim 7 wherein the stop means is spaced from the beam by an amount such that the flexing motion of the beam is substantially critically damped.

9. Apparatus as set forth in claim 7 wherein the beam is composed of an elastomeric material.

10. Apparatus as set forth in claim 9 wherein the elastorner is butyl rubber.

11. Apparatus as set forth in claim 7 wherein the beam comprises a pair of opposed L-shaped legs depending from the traverse bar; the filamentary guide means is secured to each leg adjacent the outer extent of the legs; and the stop means comprises a rigid member positioned between the legs as to be equally spaced from each leg when the legs are unfiexed.

References Cited by the Examiner UNITED STATES PATENTS 1,105 ,45 3 7/ 14 Petersen 24243 2,869,797 1/59 Clerc 24243 3,097,805 7/63 Oberly 24243 FOREIGN PATENTS 611,586 11/48 Great Britain.

MERVIN STEIN, Primary Examiner. 

1. A HIGH SPEED WINDING APPARATUS FOR COLLECTING FILAMENTARY MATERIALS ON A ROTATING PACKAGE COMPRISING: A TRAVERSE BAR DISPOSED IN A DIRECTION PARALLEL TO THE AXIS OF ROTATON OF SAID PACKAGE; MEANS FOR RECIPROCATING SAID TRAVERSE BAR IN SAID DIRECTION, FILAMENTARY GUIDE MEANS CARRIED BY SAID BAR ADJACENT THE PACKAGE, SAID GUIDE MEANS COMPRISING AN ELONGATED FLEXIBLE ELASTOMERIC PORTION PROJECTING OUTWARDLY FROM THE BAR AND MEANS MOUNTED ON THE 